Certified Flight Instructor (CFI) Practice Exam

What does Vmc indicate in aviation?

1. Maximum landing gear extension speed

2. Minimum control speed with critical engine inoperative

3. Design flap speed

4. Maximum speed in level flight with maximum continuous power

The correct answer is: Minimum control speed with critical engine inoperative

Vmc, or Minimum Control Speed with the Critical Engine Inoperative, is a crucial aerodynamic parameter for multiengine aircraft. This speed indicates the lowest airspeed at which the aircraft can maintain controlled flight with one engine inoperative. It is particularly important during takeoff and initial climb where the aircraft is most vulnerable to the effects of asymmetrical thrust. When one engine fails, the aircraft will tend to yaw towards the inoperative engine due to the loss of thrust on that side. If the aircraft's speed falls below Vmc, the pilot may not have sufficient control authority to maintain heading and counteract the yaw and roll tendencies. This could result in a loss of control, making it imperative for pilots to understand and respect this speed. In the context of aviation safety, recognizing Vmc helps pilots make informed decisions during critical phases of flight, allowing them to maintain control and navigate effectively after an engine failure.